This is one of those issues that is completely trivial and irrelevant to the function of the network, so it shouldn't bother me, but... Every time I see it, it annoys the crap out of me, and I want to fix it.
General network layout:
Router A and Router B are directly connected via serial. Router A is connected to a 2970 via Gigabit0/0. Routers A and B are both connected to a second 2970 both via Gigabit 0/1. Router B was previously connected to the first 2970 via it's own Gigabit0/0 as a redundant link, but that link is currently down. It detected the switch as a neighbor at the time.
The problem:
Routers A and B show each other as a CDP neighbor via serial. Router A shows the first 2970 (Gigabit0/0) as a neighbor. Neither Router A or B show the second 2970 (Gigabit0/1) as a CDP neighbor. However, said 2970 shows both routers as a CDP neighbor out the respective ports.
My question is... Why does CDP appear to only be functioning one-way, and how can I fix it?
General network layout:
Router A and Router B are directly connected via serial. Router A is connected to a 2970 via Gigabit0/0. Routers A and B are both connected to a second 2970 both via Gigabit 0/1. Router B was previously connected to the first 2970 via it's own Gigabit0/0 as a redundant link, but that link is currently down. It detected the switch as a neighbor at the time.
The problem:
Routers A and B show each other as a CDP neighbor via serial. Router A shows the first 2970 (Gigabit0/0) as a neighbor. Neither Router A or B show the second 2970 (Gigabit0/1) as a CDP neighbor. However, said 2970 shows both routers as a CDP neighbor out the respective ports.
My question is... Why does CDP appear to only be functioning one-way, and how can I fix it?
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